From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Thu, 23 Jun 2011 07:39:12 +0000 (+0200)
Subject: Fixed a cache collision bug. Thanks guufy1 for bugreport and test
X-Git-Tag: 2.00~1217^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2df2e89fee627a098b0192a526a2b6999699211c;p=thirdparty%2Fgrub.git

Fixed a cache collision bug. Thanks guufy1 for bugreport and test
---

diff --git a/grub-core/kern/disk.c b/grub-core/kern/disk.c
index 30bc604f0..f1456defd 100644
--- a/grub-core/kern/disk.c
+++ b/grub-core/kern/disk.c
@@ -544,6 +544,17 @@ grub_disk_read (grub_disk_t disk, grub_disk_addr_t sector,
 	    break;
 	}
 
+      if (data)
+	{
+	  grub_memcpy ((char *) buf
+		       + (agglomerate << (GRUB_DISK_CACHE_BITS
+					  + GRUB_DISK_SECTOR_BITS)),
+		       data, GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
+	  grub_disk_cache_unlock (disk->dev->id, disk->id,
+				  sector + (agglomerate
+					    << GRUB_DISK_CACHE_BITS));
+	}
+
       if (agglomerate)
 	{
 	  grub_disk_addr_t i;
@@ -568,17 +579,12 @@ grub_disk_read (grub_disk_t disk, grub_disk_addr_t sector,
 	  buf = (char *) buf 
 	    + (agglomerate << (GRUB_DISK_CACHE_BITS + GRUB_DISK_SECTOR_BITS));
 	}
-	
+
       if (data)
 	{
-	  grub_memcpy (buf, data,
-		       GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
 	  sector += GRUB_DISK_CACHE_SIZE;
 	  buf = (char *) buf + (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
 	  size -= (GRUB_DISK_CACHE_SIZE << GRUB_DISK_SECTOR_BITS);
-	  grub_disk_cache_unlock (disk->dev->id, disk->id,
-				  sector + (agglomerate
-					    << GRUB_DISK_CACHE_BITS));
 	}
     }